The differentiation states of cancer cells influence their malignant properties. Carcinoma cells lie along a continuum of less- and more-differentiated states. When taken from the same tumor, cancer cells in distinct states can have very different functional properties. For instance, in comparison to other cells in the same tumor, cancer stem cells (CSCs) efficiently seed new tumors, invade host tissues, and survive without cell-to-cell or cell-to-matrix attachments. However, basis for intrinsic therapeutic resistance, invasiveness, and other properties CSCs remains minimally understood.